package com.zzw.hj34;

import java.util.Scanner;

/**
 * @Project: hw_java
 * @Description: 图片整理
 * @Author: zzw
 */

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        String str = in.nextLine();
        char[] chars = str.toCharArray();
        for (int i = 0; i < chars.length - 1; i++) {
            for (int j = 0; j < chars.length - i - 1; j++) {
                if (chars[j] > chars[j + 1]) {
                    char temp = chars[j + 1];
                    chars[j + 1] = chars[j];
                    chars[j] = temp;
                }
            }
        }
        for (char c : chars) {
            System.out.print(c);
        }
    }
}